Back when this calculator was first created, we decided to use a non-standard definition of longitude and time zone, to make coordinate entry less awkward. So on this page, both longitude and time zone are defined as positive to the west, instead of the international standard of positive to the east of the Prime Meridian.

We maintain this page as a courtesy to those people who, for whatever reason, prefer the old calculator. Month: Day: Year e. Elevation is measured in degrees up from the horizon. If you enter decimal degrees in the degrees field, please clear the minutes and seconds fields, or they will be added in.

## Celestial Coordinates

If you select a city from the pulldown menu, the latitude, longitude and time zone fields will be filled in by the program. Otherwise the time zone associated with the selected city's Local Standard Time will be automatically entered. Selecting "Yes" in the Daylight Saving field will cause the solar position calculation to assume the current time has been adjusted forward one hour from standard time. If you are uncertain of the time zone for a location, refer to our Time Zone Table.

To perform calculations for a different date, simply select the month in the pulldown box, and enter the day and four digit year in the appropriate input boxes. Time of day for the calculation can be changed in the same way. Hit the "Calculate Solar Position" button. Once the calculations are complete, you may use your browser's "Print" function to obtain a hardcopy of the results.

Results are given in the following units: Equation of Time in minutes of time; Solar Declination in degrees, with positive to the north; Azimuth in degrees clockwise from north; Elevation in degrees up from the horizon; Cosine of Solar Zenith Angle is unitless.

Earth System Research Lab. Daylight Saving Time :. AM PM 24hr. Equation of Time minutes :. Solar Declination degrees :. Azimuth is measured in degrees clockwise from north.The vector from an observer origin to a point of interest is projected perpendicularly onto a reference plane ; the angle between the projected vector and a reference vector on the reference plane is called the azimuth. When used as a celestial coordinatethe azimuth is the horizontal direction of a star or other astronomical object in the sky.

The star is the point of interest, the reference plane is the local area e. The azimuth is the angle between the north vector and the star's vector on the horizontal plane. The concept is used in navigationastronomyengineeringmappingmining, and ballistics. There are exceptions: some navigation systems use south as the reference vector. Any direction can be the reference vector, as long as it is clearly defined.

Quite commonly, azimuths or compass bearings are stated in a system in which either north or south can be the zero, and the angle may be measured clockwise or anticlockwise from the zero.

The reference direction, stated first, is always north or south, and the turning direction, stated last, is east or west. The directions are chosen so that the angle, stated between them, is positive, between zero and 90 degrees. If the bearing happens to be exactly in the direction of one of the cardinal pointsa different notation, e. The cartographical azimuth in decimal degrees can be calculated when the coordinates of 2 points are known in a flat plane cartographical coordinates :.

Remark that the reference axes are swapped relative to the counterclockwise mathematical polar coordinate system and that the azimuth is clockwise relative to the north. This is the reason why the X and Y axis in the above formula are swapped. This is typically used in triangulation and azimuth identification AzIDespecially in radar applications. A better approximation assumes the Earth is a slightly-squashed sphere an oblate spheroid ; azimuth then has at least two very slightly different meanings.

Normal-section azimuth is the angle measured at our viewpoint by a theodolite whose axis is perpendicular to the surface of the spheroid; geodetic azimuth is the angle between north and the geodesic ; that is, the shortest path on the surface of the spheroid from our viewpoint to Point 2.

Various websites will calculate geodetic azimuth; e. Formulas for calculating geodetic azimuth are linked in the distance article. Normal-section azimuth is simpler to calculate; Bomford says Cunningham's formula is exact for any distance.

To calculate the azimuth of the sun or a star given its declination and hour angle at our location, we modify the formula for a spherical earth. There is a wide variety of azimuthal map projections. They all have the property that directions the azimuths from a central point are preserved. Some navigation systems use south as the reference plane. However, any direction can serve as the plane of reference, as long as it is clearly defined for everyone using that system.

Used in celestial navigation, an azimuth is the direction of a celestial body from the observer. In modern astronomy azimuth is nearly always measured from the north. The article on coordinate systemsfor example, uses a convention measuring from the south. In former times, it was common to refer to azimuth from the south, as it was then zero at the same time that the hour angle of a star was zero. This assumes, however, that the star upper culminates in the south, which is only true if the star's declination is less than i.

If, instead of measuring from and along the horizon, the angles are measured from and along the celestial equatorthe angles are called right ascension if referenced to the Vernal Equinox, or hour angle if referenced to the celestial meridian.Many applications, such as navigation and radio frequency engineering, require a thorough understanding of geographic calculations.

Some very natural questions seem to come up in a variety of disciplines: How far apart are two points on the Earth? What direction do I need to go to reach a particular point?

If I go in a particular direction for a certain distance, where will I end up? Visualization makes these calculations immensely easier, and to visualize you need to come up with an accurate model. As it turns out, there are two common approaches for modelling the surface of the Earth: spherical and ellipsoidal.

Another, more accurate, model is called the geoid. The geoid is a complex surface where each point on the surface has the same gravitational pull. The shape of the geoid does not lend itself well to geometric calculations and new research and measurements are constantly refining the geoidso people generally stick with either the spherical model or the ellipsoid model.

The spherical model can be very accurate under certain stringent conditions; however, the ellipsoid model is generally a very accurate model everywhere. You can think of either model as the mean sea level. So elevations, such as those on a contour map, are generally given as height above the ellipsoid. Both spherical and ellipsoid models have symmetry that allow you to do calculations, but that symmetry also means that people have to agree on a common starting point for the model.

The starting "reference" point is called a datum and there are many different datums.

### Azimuth Angle:

Transforming between datums can be very complicated depending on how you do it, and those transformations are just outside the scope of this article maybe another article will cover datums. So, the rest of this article assumes that we are working within some particular datum and there is no need to transfer the coordinates in this datum into coordinates of another datum. The good news is that we can solve a lot of geographic problems in the spherical model with a few simple mathematical tools.

Another important aspect of the spherical model is that, in terms of visualization, it covers just about everything we need; the ellipsoid model can be visualized as a refinement of the spherical model. This approach works really well because, in terms of percentages, the Earth is very close to a sphere.

This article describes each model in some depth and provides solutions to the following common geographic problems:. The spherical model is simple in mathematical terms because of its symmetry: every point on the surface is equidistant from the center, it's difficult to imagine more symmetry.

This fact has a number of very helpful consequences that can be summed up in the following statment: Geodesic paths between two points on a sphere are great circles. A geodesic path is simply the shortest path between two points along the surface. Of course, it would be shorter to go straight through the Earth between the two points, but that is generally not possible for us surface dwellers.

A great circle is just like every other circle with the additional contraint that its center lies at the center of the sphere. The following table summarizes some of the mathematical tools that are available for analyzing the spherical model:.

As with all mathematical formulas, it's important to understand where these formulas apply. For instance, lines of latitude are NOT great circles except for the equator, which is a line of latitude and a great circle and so laws of Cosines and Sines for spherical triangles do not apply to lines of latitude.Latitude and Longitude are the units that represent the coordinates at geographic coordinate system.

To make a search, use the name of a place, city, state, or address, or click the location on the map to find lat long coordinates. Just like every actual house has its address which includes the number, the name of the street, city, etcevery single point on the surface of earth can be specified by the latitude and longitude coordinates.

Therefore, by using latitude and longitude we can specify virtually any point on earth. The latitude has the symbol of phiand it shows the angle between the straight line in the certain point and the equatorial plane. The longitude has the symbol of lambda and is another angular coordinate defining the position of a point on a surface of earth.

The longitude is defined as an angle pointing west or east from the Greenwich Meridian, which is taken as the Prime Meridian. Both latitude and longitude are measured in degreeswhich are in turn divided into minutes and seconds.

You can search for a place using a city's or town's name, as well as the name of special places, and the correct lat long coordinates will be shown at the bottom of the latitude longitude finder form. At that, the place you found will be displayed with the point marker centered on map.

Also the gps coordinates will be displayed below the map. Visit Where am I now to find your current location on map.

### Distance and Azimuths Between Two Sets of Coordinates

Dear visitors, You can get free 30 geocode process per day by Signing up free to latlong. Non registered visitors can only run 10 geocode process. Thank you for supporting us Thanks for your visiting our website. Batch Multi Geocoding is available for our registered users. So you need to sign up to latlong. I see that bulk geocoding is available - but where? I have about 25 to do, but I don't want to type in each one individually. However, I don't see a button or link or anything for me to upload my 25 addresses.

Peace CJ. Dear visitors, We started user login system and this will give our users the opportunity to use latlong.

## Latitude and Longitude Finder

Hope you enjoy new features. Best regards.Volume 3 No. This paper presents a method for calculating the "look angles" or "Az-El" azimuth and elevation angles for satellite earth stations using an on-line JavaScript program. The paper provides a brief overview of the equations required for performing the calculations and concludes with the source code for the JavaScript program.

Many communication links use satellites, parked in geostationary orbit sometimes called geosynchronous for transmitting information regionally and globally.

Geostationary means that the satellite is located at a fixed point approximately 22, miles in altitude above the equator. At this altitude, the gravitational pulls of the earth, sun and the moon work together along with the centrifugal force caused by the satellites rotation around the earth to keep the satellite at a fixed location above the earth.

Of course the satellite does drift it moves in a figure eight pattern and must be periodically repositioned using on-board power thrusters for maintaining the optimum location. But for us on earth, the satellite appears to be stationary. Included in the earth station are items such as the exciter, the high power TWTA's - traveling wave tube amplifiers also called HPA's - high power amplifiersthe receivers and a parabolic shaped reflector which is pointing at the satellites parked in geostationary orbit.

The satellites require a payload of antennae, transponders combination receive and transmit units and attitude controls for maintaining the location in geostationary orbit. Orbital corrections station keeping on the satellite are made approximately every two to six weeks. The longitudinal position is referenced to earth at the sub-satellite point. The minimum spacing of the satellites is currently 2 degrees.

Geostationary satellite communications has many advantages over terrestrial microwave communications and low-orbit satellites. The geostationary satellite position is fixed with respect to earth. Secondly, the path to and from the satellite is always available except during certain weather conditions and solar disturbances. Additionally, the satellites transmission back to earth covers a very large area footprint which allows simultaneous transmission to many sites.

**The Sky Part 1: Local Sky and Alt-Az / Horizon Coordinates**

Some disadvantages to geostationary satellites are propagation delays because of the distance to and from the satellite approximately 44, miles round trip. Satellite transmitters require more power because of the increased distance increased path loss resulting in a significant increase in the transmitter costs.

It is difficult to fabricate high power amplifiers which operate at high frequencies. The last disadvantage is that there is a significant cost in maintaining a satellite parked in geostationary orbit.This Java Script calculator by Stephen R. Schmitt converts celestial coordinates of right ascension and declination into horizon coordinates of altitude and azimuth. To operate the calculator, enter the right ascension and declination of a celestial object, enter the latitude and longitude of the observing site.

Enter north and east degrees as positive integers; enter south and west degrees as negative integers; enter minutes as positive floating point numbers. Enter the date and time for your location. If the date and time zone of your computer is set correctly, the program will compute the correct universal time UT.

Press the Compute button to obtain the solution for your location and selected time. On invalid entries, a popup window will display an error message. The Test button inserts a test case to show how the calculator works. The coordinates of stars, planets, and other celestial objects corresponding to latitude and longitude are declination DEC and right ascension RA. The declination of an object is its angle in degrees, minutes, and seconds of arc above or below the celestial equator.

The right ascension is the angle between an object and the location of the vernal equinox First Point in Aries measured eastward along the celestial equator in hours, minutes, and seconds of sidereal time. Since the location of the vernal equinox changes due to the precession of the Earth's axis of rotation, coordinates must be given with reference to a date or epoch.

Right ascension is given in time units. As the Earth rotates, the sky moves to the West by about 1 hour of right ascension during each hour of clock time or exactly one hour of sidereal time. The Earth makes one full revolution in about 23 hours and 56 minutes of clock time or 24 hours of sidereal time. Sidereal time corresponds to the right ascension of the zenith, the point in the sky directly overhead.

Horizon coordinates: azimuth and altitude This is a local coordinate system to use for locating objects in the night sky as seen from a point on the Earth's surface. Azimuth is the angle of a celestial object around the sky from north. Altitude is the complement of the zenith angle, which is the angle from the local meridian to the hour circle of object being observed. Generally, refraction makes objects near the horizon appear higher than their computed altitude.

It is used in coordinate conversion. Custom Search. Coordinates of object and observer. Notes Equatorial coordinates By extending the lines of latitude and longitude outward from the Earth and onto the inside of the celestial sphere we get the equatorial coordinate system.By using our site, you acknowledge that you have read and understand our Cookie PolicyPrivacy Policyand our Terms of Service. It only takes a minute to sign up. I was wondering if there is a way to calculate the Latitude and Longitude of a given point provided you know the range, azimuth, and elevation of said point?

Please take a look at this link. Sign up to join this community. The best answers are voted up and rise to the top. Home Questions Tags Users Unanswered. Asked 8 years, 8 months ago. Active 2 years, 1 month ago.

Viewed 7k times. Ramhound Ramhound 1 1 silver badge 9 9 bronze badges. Maybe but this is not the right site to ask the question. Take a look here. Ram: I didn't downvote it. I voted to close. I am not the dictionary for StackExchange network so you can gladly go to www. The close reason only shows about 4 choices so I voted to close as off-topic. This has nothing to do with C for starters and you are asking basically a geographical math question which has nothing to do with programming.

But you can start next time by losing the piss poor attitude. Dyppl - I appreciate the assistance. Ram: It has nothing to do with C because there is nowhere in the question where you ask about C other than the tag which means nothing in this case.

It should be tagged as algorithm. The cases you cited had code or referenced a particular framework. You do neither. That's not the right way to ask a question around here. I can't migrate it so you will have to delete it. Active Oldest Votes.

Taken off the page. Jethro Jethro. This was exactly what I was looking for. Glad I could help. Looks like some crazy crazy stuff.

Would hate to try and write that in C. Good luch with your project. I plan to attempt to PInvoke the dll. If I am able to determine how it works in more detail I will update my question. The link is broken, here is the new one: sourceforge. Sign up or log in Sign up using Google.

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